Air conditioning apparatus



Nov. 15, 1960 Filed Dec. 3, 1956 E. J. BURKE 2,959,933

AIR CONDITIONING APPARATUS 2 Sheets-Sheet 1 FIG.

INVENTOR.

EDWARD J. BURKE.

Max

ATTORNEY.

Nov. 15, 1960 E. J. BURKE AIR conozwronmc APPARATUS 2 Sheets-Sheet 2Filed Dec. 5, 1956 FIG. 2

INVENTOR. EDWARD J. BURKE.

ATTORNEY.

United States Patent O AIR CONDITIONING APPARATUS Edward J. Burke, NorthSyracuse, N.Y., assignor to Carrier Corporation, Syracuse, N .Y., acorporation Delaware Filed Dec. 3, 1956, Ser. No. 625,890

Claims. (Cl. 62-183) This invention relates to air conditioningequipment and more particularly to air conditioning equipment of thetype equipped with a refrigeration system operable under the reversecycle principle. Still more particularly this invention relates to airconditioning equipment more commonly known as a heat pump.

In apparatus of the type described, a heating effect as well as acooling effect, is obtained with the same equipment. This situationoccurs by virtue of the presence of a reversing valve for re-routingrefrigerant through portions of the system so that the heat transferfunctions of the evaporator and condenser are interchanged.

One of the difficulties involved in employing equipment of this type isencountered in those geographical locations wherein the outside airtemperature drops to 40 F. and below. With equipment of the type underconsideration, heat is extracted from the ambient when the apparatus isoperated on the heating cycle and is rejected in a heat exchange unitlocated in an enclosure such as a residential home. The quantity of heatavailable in the ambient at the temperature mentioned above, is limited.It is accordingly the chief object of this invention to provide airconditioning apparatus constructed so that an additional supply of heat,available by virtue of operation of certain components of the system, isutilized to increase the heat output of the unit when the latter isoperating during a portion of the range of operation of the heatingcycle.

It is another object of this invention to provide an improved airconditioning unit wherein the heat generated by the compressor, themotor driving the compressor and the electrical components forming thecontrol system for the unit is made available for incorporation into thesystem under certain operating conditions.

It is a further object of this invention to provide an air conditioningunit wherein means are provided for selectively dissipating the heatgenerated from the above sources when the unit is operating on thecooling cycle and for utilizing the heat during operation on a portionof the heating cycle. An additional object of this invention is theprovision of an improved method of operating an air conditioning unitwherein heat from the above mentioned sources is available for use inthe system during a portion of the heating cycle range and is rejectedto the atmosphere or any convenient cooling medium during the coolingcycle.

These, and other objects of the invention will be apparent upon aperusal of the ensuing specification wherein the invention isillustrated in connection with a description of an air conditioning unitor machine having a refrigerating system wherein certain components,such as the compressor and outside coil are located remotely from thelocation of the inside coil and which are provided with an enclosurehaving a compressor coinpartment separate from a coil compartment. Meansare provided for placing the two compartments in communication duringthe cooling cycle and for isolating the two compartments during theheating cycle.

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Figure l is a diagrammatic view of an air conditioning systemconstructed in accordance with this invention, wherein the componentsare illustrated during heating cycle operation;

Figure 2 is a diagrammatic view of a compressor and outside coilassembly of the type employed in this invention, wherein the componentsare illustrated during cooling cycle operation;

Figure 3 is a view similar to Figure 2 showing the outside coil andcompressor assembly in an isometric view;

Figure 4 is a fragmentary view of a partition in the compressor-outsidecoil assembly dividing the assembly into a compressor compartment and acoil compartment;

Figure 5 is a view taken along lines V-V on Figure 4 showing theconnection between a door or damper in said partition and the partition;and

Figure 6 is a view in perspective of one of the ele ments for connectingthe damper to the partition.

This invention is best illustrated by reference to an air conditioningunit known as a two-piece air-to-air heat pump which incorporates arefrigeration system operable under the reverse cycle principle. Theunit illustrated in the drawings contemplates an inside coil disposedwithin an air supply duct in a building and an outside coil andcompressor assembly housed in an enclosure provided with openings forthe flow of air therethrough. It will be appreciated that the outsidecoil and the compressor could be mounted within the same casing as theinside coil as long as proper insulation between the two sub assembliescould be maintained. While the invention is described as it applies to atwo-piece system, it will be obvious that the invention could beincorporated in an air conditioning unit of the type known as a roomcooler.

The air conditioning unit includes a refrigeration systenicomprising acompressor 10, discharge line 11, a reversing valve 12 and an outsidecoil 13 which functions as a condenser during the cooling cycle. Fan 14is employed to pass air in heat exchange relation with the coil 13 sothat when the unit is operating on a cooling cycle, hot gaseousrefrigerant discharged from the compressor and flowing to the coil 13through line 11 and valve 12 is converted to the liquid phase as heat isextracted by air moving under the influence of fan 14. The refrigerantin the coil 13 flows through line 15 to an expansion member 16, shown inthe form of a conventional thermal expansion valve having an equalizerline 16, where it flows to the indoor coil 17, functioning as anevaporator on the cooling cycle, and is passed in heat exchange relationwith a supply of air moving under the influence of fan 23. This latterheat exchange action causes the refrigerant to vaporize and pass throughline 18, reversing valve 12 and suction line 19 to compressor 10 tocom-. plete the cycle. duct forming a part of an air supply duct systemfor providing conditioned air to an enclosure or group of enclosures.

When it is desired to obtain a heating effect within line 18 to the coil17 where it is liquified 'by the heat.

transfer action promulgated by fan 23.' Liquid-refrigerant so formedflows through bypass line 21 and ex pansion valve 22 equipped withequalizer line 22 to.v the outside coil 13 through line 15. Liquidrefrigerant 2,959,933 Patented Nov. 15, 196i),

The coil 17 is usually mounted ma in coil 13 is converted to the vaporphase as ambient air is passed over the coil by the fan 14. The vaporousrefrigerant formed in this coil flows to reversing valve 12 and line 19to the compressor 10. It will be appreciated that in order to create apressure condition within the coil 13, sufficient to cause a flow ofheat from the ambient air at relatively low temperatures, it isnecessary for the compressor to draw a very low suction temperature.Under circumstances described in the above co-pending application, acoating of frost will accumulate on coil 13. A defrost control of thetype described in the co-pending application functions to temporarilyreverse the operating cycle of the unit to permit hot gas from thecompressor to flow in the coil 13.

This invention contemplates utilizing the heat available by virtue ofthe operation of the compressor and the motor driving the compressor aswell as the radiant heat by any control elements located within thesystem, in the system so that the operating efficiency will be increasedon the heating cycle. This is achieved through a unique orientation ofthe outside coil and compressor. Referring more particularly to Figure2, the compressor and the outside coil are mounted within a housing 20having a central partition 28. This partition or wall co-operates with atube sheet 29 on the outside coil assembly to divide the housing into aninsulated compressor compartment and a coil compartment. It will beappreciated that partition 28 could extend from wall to wall of theenclosure, if desired. Communication between the two compartments isachieved by virtue of an opening 30 located in the partition 28. Theopening is controlled with a closure member or damper 31 having a uniquemounting which automatically selectively permits and preventscommunication between the two compartments in a manner to be laterdescribed.

Referring more particularly to Figures 4, 5, and 6, it will be observedthat the opposite sides of the damper r closure member are provided withdiametrically opposed notches 31'. Mounted within these notches aremounting members 32 and 34 of a similar construction and comprising astrip of bimetallic material coiled in the manner shown in Figure sothat tabs 33 and 35 adapted to be secured to the damper are presented.Cooperating with the mounting elements 32 and 34 are support pieces 36and 38 formed in the manner shown in Figure 6 wherein two opposed sidesare disposed opposite one another in spaced relation and are connectedby a bend portion. One of the sides of the members 36 and 38 is providedwith an extension 37 adapted to be secured to the partition 28 in themanner shown in Figure 4. The central rectilinear portion 60 of themembers 32 and 34 is positioned between the sides of the members 34 and36 and is secured thereto by a crimping or swaging action or if desired,by a.- simple frictional bond.

The bimetallic members 32 and 34 sense the temperature in the coilcompartment as well as in the compressor compartment. Therefore thetemperature of the bimetallic members will usually be somewhere betweenthe compressor compartment temperature and coil compartment temperature.It will thus be obvious that the position of the damper will beinfluenced by the temperature of each compartment. When the resultanttemperature of the members is about 50 F. or below, the damper willclose, and when the resultant temperature is above 50 F., the damperwill open. Stop members may be placed on the partition so that portionsthereof project over one side of the opening. These members restrain therotational movement of the damper in one direction to overcome any freeswinging action of the damper.

Considering the operation of the air conditioning unit illustrating thisinvention, the bimetallic mounting pieces 32 and 34 are constructed soas to flex at a control temperature of about 50 F. or below to aposition such that the closure member prevents communication between thecompressor compartment and the coil compartment in the enclosure 20.Thus the flow of air under the influence of fan 14 is in a substantiallystraight path. When the effective temperature controlling the operationof the damper exceeds 50 F., the bimetallic mounting elements beingfixed at portion 60 flex to rotate the damper 31 so as to permitcommunication between the compressor compartment and the coilcompartment. Thus, air flowing into the housing 20 through inlet 47under the influence of fan 14 is free to circulate in the manner shownby the arrows in Figure 2 through the compressor compartment of theenclosure and into the inlet of the scroll 42 from where it issubsequently discharged through outlet 46 of the enclosure. This actioncauses the components in the compressor compartment to be cooled. Thefan 14 is mounted on a shaft 44 secured to motor 46' mounted on theoutside of the enclosure 20. When the control temperature drops below 50F., or any other conveniently selected temperature, the door or closuremember 31 closes under the influence of the movement of the bimetallicmounting elements so that the radiant heat generated by the compressorand the motor driving the compressor is trapped in the insulatedcompressor compartment. Thus instead of having the compressor and motorcooled by the air flowing in the enclosure, the elements are operated ata higher temperature. The system then operates at a higher dischargetemperature which in turn provides higher temperature refrigerant forliquification in the coil 17 serving the inside of the enclosure beingheated.

The individual control elements may be located within a box 50 withinthe compressor compartment so that any radiant effect from theseelements may likewise be made available to the refrigerant in thesystem.

Thus it will be evident that the operation of the air conditioning unitincorporating the refrigeration system in accordance with this inventionmay operate on a heating cycle at a higher temperature level and thusprovide a greater heating effect.

Summarizing it will be obvious that this invention has reduced the heatlosses in the system under certain thermal conditions. While it isappreciated that these heat losses permit efiicient operation of theunit on the cooling cycle, conservation of these losses during operationunder the heating cycle enables the increased efficiencies set out aboveto be achieved.

While I have described a preferred embodiment of the invention, it willbe understood that the invention is not limited thereto since it may beotherwise embodied within the scope of the following claims.

I claim:

1. Air conditioning apparatus comprising a first heat exchange coil, acompressor, and a second heat exchange coil, connected to form a circuitfor the flow of refrigerant, means for reversing the flow of refrigerantthrough a portion of the circuit to interchange the heat transferfunctions of the coils, an enclosure having an inlet and outlet forhousing said compressor and said second heat exchange coil, partitionmeans serving to divide the enclosure into a coil compartment containingthe inlet and outlet and a compressor compartment, said partition havingan opening therein, means providing a path of flow for a heat transfermedium over the coil in said coil compartment, and means for selectivelyrejecting to and isolating from the medium, heat generated by operationof the compressor, said last mentioned means being operable in responseto a predetermined temperature of the medium.

2. The invention set forth in claim 1 wherein said last mentioned meansincludes a door and thermally responsive means controlling movement ofthe door.

3. The invention set forth in claim 1 wherein said last mentioned meansis operable when said first heat exchange coil is rejecting heat.

4. An air conditioning unit comprising a refrigeration system includinga compressor, a first heat transfer coil and a second heat transfer coilconnected to form a closed circuit for the flow of refrigerant, meansinterposed in said system for reversing the flow of refrigerant througha portion of the circuit to interchange the functions of the heattransfer coils, a housing surrounding the compressor and one of saidheat transfer coils, a partition, having an opening, positioned in saidhousing to separate the housing into a compressor compartment and a heattransfer coil compartment, a door in said partition controlling saidopening, means for supplying a heat transfer medium to said coil in saidenclosure, and means for controlling the operation of the door toselectively direct a pontion of the flow of the heat transfer mediuminto the compressor compartment or isolate the compressor compartmentfrom the flow of the medium whereby the heat generated by the compressoris trapped and utilized to increase the operating temperature of therefrigerant flowing through the compressor.

5. A refrigeration system including a compressor, a first heat transfercoil, a second heat transfer coil connected to form a circuit for theflow of refrigerant, means for reversing refrigerant flow in a portionof the circuit to interchange the function of the heat transfer coils, acompantmented housing accommodating one of said coils and thecompressor, means for supplying a medium in heat transfer relation withthe coil in said housing and means for selectively including thecompressor in the path of flow of said medium through said housing orexcluding the compressor from said path whereby the heat generated bythe compressor is employed to raise the operating temperature of therefrigerant flowing through the compressor.

References Cited in the file of this patent UNITED STATES PATENTS

